def syscall_init(mem, breakpoint, argv, debug):
#---------------------------------------------------------------------
# memory map initialization
#---------------------------------------------------------------------
# TODO: for multicore allocate 8MB for each process
#proc_stack_base[pid] = stack_base - pid * 8 * 1024 * 1024
# top of heap (breakpoint) # TODO: handled in load program
# memory maps: 1GB above top of heap
# mmap_start = mmap_end = break_point + 0x40000000
#---------------------------------------------------------------------
# stack argument initialization
#---------------------------------------------------------------------
# http://articles.manugarg.com/aboutelfauxiliaryvectors.html
#
# contents size
#
# 0x7FFF.FFFF [ end marker ] 4 (NULL)
# [ environment str data ] >=0
# [ arguments str data ] >=0
# [ padding ] 0-16
# [ auxv[n] data ] 8 (AT_NULL Vector)
# 8*x
# [ auxv[0] data ] 8
# [ envp[n] pointer ] 4 (NULL)
# 4*x
# [ envp[0] pointer ] 4
# [ argv[n] pointer ] 4 (NULL)
# 4*x
# [ argv[0] pointer ] 4 (program name)
# stack ptr-> [ argc ] 4 (size of argv)
#
# (stack grows down!!!)
#
# 0x7F7F.FFFF < stack limit for pid 0 >
#
# auxv variables initialized by gem5, are these needed?
#
# - PAGESZ: system page size
# - PHDR: virtual addr of program header tables
# (for statically linked binaries)
# - PHENT: size of program header entries in elf file
# - PHNUM: number of program headers in elf file
# - AT_ENRTY: program entry point
# - UID: user ID
# - EUID: effective user ID
# - GID: group ID
# - EGID: effective group ID
# TODO: handle auxv, envp variables
auxv = []
envp = []
argc = len(argv)
def sum_(x):
val = 0
for i in x:
val += i
return val
# calculate sizes of sections
# TODO: parameterize auxv/envp/argv calc for variable int size?
stack_nbytes = [
4, # end mark nbytes
sum_([len(x) + 1 for x in envp]), # envp_str nbytes
sum_([len(x) + 1 for x in argv]), # argv_str nbytes
0, # padding nbytes
8 * (len(auxv) + 1), # auxv nbytes
4 * (len(envp) + 1), # envp nbytes
4 * (len(argv) + 1), # argv nbytes
4
] # argc nbytes
# calculate padding to align boundary
# TODO: gem5 doesn't do this step, temporarily remove it. There should
# really be padding to align argv to a 16 byte boundary!!!
#stack_nbytes[3] = 16 - (sum_(stack_nbytes[:3]) % 16)
def round_down(val):
return val & ~(page_size - 1)
# calculate stack pointer based on size of storage needed for args
# TODO: round to nearest page size?
stack_ptr = round_down(stack_base - sum_(stack_nbytes))
offset = stack_ptr + sum_(stack_nbytes)
stack_off = []
for nbytes in stack_nbytes:
offset -= nbytes
stack_off.append(offset)
assert offset == stack_ptr
#print 'stack min', hex( stack_ptr )
#print 'stack size', stack_base - stack_ptr
#print 'argv', stack_nbytes[-2]
#print 'envp', stack_nbytes[-3]
#print 'auxv', stack_nbytes[-4]
#print 'argd', stack_nbytes[-6]
#print 'envd', stack_nbytes[-7]
# utility functions
# TODO: we can do more efficient versions of these using Memory object
# (writing 4 bytes at once etc.)
def str_to_mem(mem, val, addr):
for i, char in enumerate(val + '\0'):
mem.write(addr + i, 1, ord(char))
return addr + len(val) + 1
def int_to_mem(mem, val, addr):
# TODO properly handle endianess
for i in range(4):
mem.write(addr + i, 1, (val >> 8 * i) & 0xFF)
return addr + 4
# write end marker to memory
int_to_mem(mem, 0, stack_off[0])
# write environment strings to memory
envp_ptrs = []
offset = stack_off[1]
for x in envp:
envp_ptrs.append(offset)
offset = str_to_mem(mem, x, offset)
assert offset == stack_off[0]
# write argument strings to memory
argv_ptrs = []
offset = stack_off[2]
for x in argv:
argv_ptrs.append(offset)
offset = str_to_mem(mem, x, offset)
assert offset == stack_off[1]
# write auxv vectors to memory
offset = stack_off[4]
for type_, value in auxv + [(0, 0)]:
offset = int_to_mem(mem, type_, offset)
offset = int_to_mem(mem, value, offset)
assert offset == stack_off[3]
# write envp pointers to memory
offset = stack_off[5]
for env in envp_ptrs + [0]:
offset = int_to_mem(mem, env, offset)
assert offset == stack_off[4]
# write argv pointers to memory
offset = stack_off[6]
for arg in argv_ptrs + [0]:
offset = int_to_mem(mem, arg, offset)
assert offset == stack_off[5]
# write argc to memory
offset = stack_off[7]
offset = int_to_mem(mem, argc, offset)
assert offset == stack_off[6]
# initialize processor state
state = State(mem, debug, reset_addr=0x1000)
# TODO: where should this go?
state.breakpoint = breakpoint
#print '---'
#print 'argc = %d (%x)' % ( argc, stack_off[-1] )
#for i, ptr in enumerate(argv_ptrs):
# print 'argv[%d] = %x (%x)' % ( i, argv_ptrs[i], stack_off[-2]+4*i ),
# print len( argv[i] ), argv[i]
#print 'argd = %s (%x)' % ( argv[0], stack_off[-6] )
#print '---'
#print 'argv-base', hex(stack_off[-2])
#print 'envp-base', hex(stack_off[-3])
#print 'auxv-base', hex(stack_off[-4])
#print 'argd-base', hex(stack_off[-6])
#print 'envd-base', hex(stack_off[-7])
# initialize processor registers
state.rf[reg_map['a0']] = argc # argument 0 reg = argc
state.rf[reg_map['a1']] = stack_off[6] # argument 1 reg = argv ptr addr
state.rf[reg_map['sp']] = stack_ptr # stack pointer reg
return state
def syscall_init(mem, entrypoint, breakpoint, argv, envp, debug):
#---------------------------------------------------------------------
# memory map initialization
#---------------------------------------------------------------------
# TODO: for multicore allocate 8MB for each process
#proc_stack_base[pid] = stack_base - pid * 8 * 1024 * 1024
# top of heap (breakpoint) # TODO: handled in load program
# memory maps: 1GB above top of heap
# mmap_start = mmap_end = break_point + 0x40000000
#---------------------------------------------------------------------
# stack argument initialization
#---------------------------------------------------------------------
# http://articles.manugarg.com/aboutelfauxiliaryvectors.html
#
# contents size
#
# 0x7FFF.FFFF [ end marker ] 4 (NULL)
# [ environment str data ] >=0
# [ arguments str data ] >=0
# [ padding ] 0-16
# [ auxv[n] data ] 8 (AT_NULL Vector)
# 8*x
# [ auxv[0] data ] 8
# [ envp[n] pointer ] 4 (NULL)
# 4*x
# [ envp[0] pointer ] 4
# [ argv[n] pointer ] 4 (NULL)
# 4*x
# [ argv[0] pointer ] 4 (program name)
# stack ptr-> [ argc ] 4 (size of argv)
#
# (stack grows down!!!)
#
# 0x7F7F.FFFF < stack limit for pid 0 >
#
# auxv variables initialized by gem5, are these needed?
#
# - PAGESZ: system page size
# - PHDR: virtual addr of program header tables
# (for statically linked binaries)
# - PHENT: size of program header entries in elf file
# - PHNUM: number of program headers in elf file
# - AT_ENRTY: program entry point
# - UID: user ID
# - EUID: effective user ID
# - GID: group ID
# - EGID: effective group ID
# TODO: handle auxv, envp variables
auxv = []
if EMULATE_GEM5:
argv = argv[1:]
argc = len(argv)
def sum_(x):
val = 0
for i in x:
val += i
return val
# calculate sizes of sections
# TODO: parameterize auxv/envp/argv calc for variable int size?
stack_nbytes = [
4, # end mark nbytes (sentry)
sum_([len(x) + 1 for x in envp]), # envp_str nbytes
sum_([len(x) + 1 for x in argv]), # argv_str nbytes
0, # padding nbytes
8 * (len(auxv) + 1), # auxv nbytes
4 * (len(envp) + 1), # envp nbytes
4 * (len(argv) + 1), # argv nbytes
4
] # argc nbytes
if EMULATE_SIMIT:
stack_nbytes[4] = 0 # don't to auxv for simit
def round_up(val):
alignment = 16
return (val + alignment - 1) & ~(alignment - 1)
# calculate padding to align boundary
# NOTE: MIPs approach (but ignored by gem5)
#stack_nbytes[3] = 16 - (sum_(stack_nbytes[:3]) % 16)
# NOTE: gem5 ARM approach
stack_nbytes[3] = round_up(sum_(stack_nbytes)) - sum_(stack_nbytes)
if EMULATE_SIMIT:
stack_nbytes[3] = 0
def round_down(val):
alignment = 16
return val & ~(alignment - 1)
# calculate stack pointer based on size of storage needed for args
# TODO: round to nearest page size?
stack_ptr = round_down(stack_base - sum_(stack_nbytes))
if EMULATE_SIMIT:
stack_ptr = stack_base - MAX_ENVIRON
offset = stack_ptr + sum_(stack_nbytes)
# FIXME: this offset seems really wrong, but this is how gem5 does it!
if EMULATE_GEM5:
offset = stack_base
print "XXX", offset
stack_off = []
for nbytes in stack_nbytes:
offset -= nbytes
stack_off.append(offset)
# FIXME: this is fails for GEM5's hacky offset...
if not EMULATE_GEM5:
assert offset == stack_ptr
if debug.enabled('bootstrap'):
print 'stack base', hex(stack_base)
print 'stack min ', hex(stack_ptr)
print 'stack size', stack_base - stack_ptr
print
print 'sentry ', stack_nbytes[0]
print 'env d ', stack_nbytes[1]
print 'arg d ', stack_nbytes[2]
print 'padding', stack_nbytes[3]
print 'auxv ', stack_nbytes[4]
print 'envp ', stack_nbytes[5]
print 'argv ', stack_nbytes[6]
print 'argc ', stack_nbytes[7]
# utility functions
def str_to_mem(mem, val, addr):
for i, char in enumerate(val + '\0'):
mem.write(addr + i, 1, ord(char))
return addr + len(val) + 1
def int_to_mem(mem, val, addr):
# TODO properly handle endianess
for i in range(4):
mem.write(addr + i, 1, (val >> 8 * i) & 0xFF)
return addr + 4
# write end marker to memory
int_to_mem(mem, 0, stack_off[0])
# write environment strings to memory
envp_ptrs = []
offset = stack_off[1]
for x in envp:
envp_ptrs.append(offset)
offset = str_to_mem(mem, x, offset)
assert offset == stack_off[0]
# write argument strings to memory
argv_ptrs = []
offset = stack_off[2]
for x in argv:
argv_ptrs.append(offset)
offset = str_to_mem(mem, x, offset)
assert offset == stack_off[1]
# write auxv vectors to memory
offset = stack_off[4]
if not EMULATE_SIMIT:
for type_, value in auxv + [(0, 0)]:
offset = int_to_mem(mem, type_, offset)
offset = int_to_mem(mem, value, offset)
assert offset == stack_off[3]
# write envp pointers to memory
offset = stack_off[5]
for env in envp_ptrs + [0]:
offset = int_to_mem(mem, env, offset)
assert offset == stack_off[4]
# write argv pointers to memory
offset = stack_off[6]
for arg in argv_ptrs + [0]:
offset = int_to_mem(mem, arg, offset)
assert offset == stack_off[5]
# write argc to memory
offset = stack_off[7]
offset = int_to_mem(mem, argc, offset)
assert offset == stack_off[6]
# write zeros to bottom of stack
# TODO: why does gem5 do this?
offset = stack_off[7] - 1
while offset >= stack_ptr:
mem.write(offset, 1, ord('\0'))
offset -= 1
# initialize processor state
state = State(mem, debug, reset_addr=0x1000)
if debug.enabled('bootstrap'):
print '---'
#print 'argc = %d (%x)' % ( argc, stack_off[-1] )
#for i, ptr in enumerate(argv_ptrs):
# print 'argv[%2d] = %x (%x)' % ( i, argv_ptrs[i], stack_off[-2]+4*i ),
# print len( argv[i] ), argv[i]
#print 'argd = %s (%x)' % ( argv[0], stack_off[-6] )
print '---'
print 'envd-base', hex(stack_off[-7])
print 'argd-base', hex(stack_off[-6])
print 'auxv-base', hex(stack_off[-4])
print 'envp-base', hex(stack_off[-3])
print 'argv-base', hex(stack_off[-2])
print 'argc-base', hex(stack_off[-1])
print 'STACK_PTR', hex(stack_ptr)
# TODO: where should this go?
#state.pc = entrypoint
state.breakpoint = r_uint(breakpoint)
# initialize processor registers
state.rf[0] = 0 # ptr to func to run when program exits, disable
state.rf[1] = stack_off[6] # argument 1 reg = argv ptr addr
state.rf[2] = stack_off[5] # argument 2 reg = envp ptr addr
if EMULATE_SIMIT:
state.rf[1] = argc # argument 1 reg = argc
state.rf[2] = stack_off[6] # argument 2 reg = argv ptr addr
state.rf[13] = stack_ptr # stack pointer reg
state.rf[15] = entrypoint # program counter
if debug.enabled('bootstrap'):
state.rf.print_regs(per_row=4)
print '=' * 20, 'end bootstrap', '=' * 20
return state
def syscall_init( mem, breakpoint, argv, envp, debug ):
#---------------------------------------------------------------------
# stack argument initialization
#---------------------------------------------------------------------
# http://articles.manugarg.com/aboutelfauxiliaryvectors.html
#
# contents size
#
# 0x7FFF.FFFF [ end marker ] 8 (NULL)
# [ environment str data ] >=0
# [ arguments str data ] >=0
# [ padding ] 0-16
# [ auxv[n] data ] 8 (AT_NULL Vector)
# 8*x
# [ auxv[0] data ] 8
# [ envp[n] pointer ] 8 (NULL)
# 8*x
# [ envp[0] pointer ] 8
# [ argv[n] pointer ] 8 (NULL)
# 8*x
# [ argv[0] pointer ] 8 (program name)
# stack ptr-> [ argc ] 8 (size of argv)
#
# (stack grows down!!!)
#
# 0x7F7F.FFFF < stack limit for pid 0 >
#
# auxv variables initialized by gem5, are these needed?
#
# - PAGESZ: system page size
# - PHDR: virtual addr of program header tables
# (for statically linked binaries)
# - PHENT: size of program header entries in elf file
# - PHNUM: number of program headers in elf file
# - AT_ENRTY: program entry point
# - UID: user ID
# - EUID: effective user ID
# - GID: group ID
# - EGID: effective group ID
# TODO: handle auxv, envp variables
auxv = []
argc = len( argv )
def sum_( x ):
val = 0
for i in x:
val += i
return val
# calculate sizes of sections
# TODO: parameterize auxv/envp/argv calc for variable int size?
stack_nbytes = [ 8, # end mark nbytes
sum_([len(x)+1 for x in envp]), # envp_str nbytes
sum_([len(x)+1 for x in argv]), # argv_str nbytes
0, # padding nbytes
16*(len(auxv) + 1), # auxv nbytes
8*(len(envp) + 1), # envp nbytes
8*(len(argv) + 1), # argv nbytes
8 ] # argc nbytes
# calculate padding to align boundary
# TODO: gem5 doesn't do this step, temporarily remove it. There should
# really be padding to align argv to a 16 byte boundary!!!
#stack_nbytes[3] = 16 - (sum_(stack_nbytes[:3]) % 16)
def round_down( val ):
return val & ~(page_size - 1)
# calculate stack pointer based on size of storage needed for args
# TODO: round to nearest page size?
stack_ptr = round_down( stack_base - sum_( stack_nbytes ) )
offset = stack_ptr + sum_( stack_nbytes )
stack_off = []
for nbytes in stack_nbytes:
offset -= nbytes
stack_off.append( offset )
assert offset == stack_ptr
#print 'stack min', hex( stack_ptr )
#print 'stack size', stack_base - stack_ptr
#print 'argv', stack_nbytes[-2]
#print 'envp', stack_nbytes[-3]
#print 'auxv', stack_nbytes[-4]
#print 'argd', stack_nbytes[-6]
#print 'envd', stack_nbytes[-7]
# utility functions
def str_to_mem( mem, val, addr ):
for i, char in enumerate(val+'\0'):
mem.write( addr + i, 1, ord( char ) )
return addr + len(val) + 1
def int_to_mem( mem, val, addr ):
# TODO properly handle endianess
for i in range( 8 ):
mem.write( addr+i, 1, (val >> 8*i) & 0xFF )
return addr + 8
# write end marker to memory
int_to_mem( mem, 0, stack_off[0] )
# write environment strings to memory
envp_ptrs = []
offset = stack_off[1]
for x in envp:
envp_ptrs.append( offset )
offset = str_to_mem( mem, x, offset )
assert offset == stack_off[0]
# write argument strings to memory
argv_ptrs = []
offset = stack_off[2]
for x in argv:
argv_ptrs.append( offset )
offset = str_to_mem( mem, x, offset )
assert offset == stack_off[1]
# write auxv vectors to memory
offset = stack_off[4]
for type_, value in auxv + [(0,0)]:
offset = int_to_mem( mem, type_, offset )
offset = int_to_mem( mem, value, offset )
assert offset == stack_off[3]
# write envp pointers to memory
offset = stack_off[5]
for env in envp_ptrs + [0]:
offset = int_to_mem( mem, env, offset )
assert offset == stack_off[4]
# write argv pointers to memory
offset = stack_off[6]
for arg in argv_ptrs + [0]:
offset = int_to_mem( mem, arg, offset )
assert offset == stack_off[5]
# write argc to memory
offset = stack_off[7]
offset = int_to_mem( mem, argc, offset )
assert offset == stack_off[6]
# initialize processor state
state = State( mem, debug, reset_addr=0x10000 )
# TODO: where should this go?
state.breakpoint = r_uint( breakpoint )
#print '---'
#print 'argc = %d (%x)' % ( argc, stack_off[-1] )
#for i, ptr in enumerate(argv_ptrs):
# print 'argv[%d] = %x (%x)' % ( i, argv_ptrs[i], stack_off[-2]+4*i ),
# print len( argv[i] ), argv[i]
#print 'argd = %s (%x)' % ( argv[0], stack_off[-6] )
#print '---'
#print 'argv-base', hex(stack_off[-2])
#print 'envp-base', hex(stack_off[-3])
#print 'auxv-base', hex(stack_off[-4])
#print 'argd-base', hex(stack_off[-6])
#print 'envd-base', hex(stack_off[-7])
# initialize processor registers
state.rf[ reg_map['a0'] ] = argc # argument 0 reg = argc
state.rf[ reg_map['a1'] ] = stack_off[6] # argument 1 reg = argv ptr addr
state.rf[ reg_map['sp'] ] = stack_ptr # stack pointer reg
return state
# instantiate architectural state with memory and reset address
return state
def syscall_init( mem, entrypoint, breakpoint, argv, envp, debug ):
#---------------------------------------------------------------------
# memory map initialization
#---------------------------------------------------------------------
# TODO: for multicore allocate 8MB for each process
#proc_stack_base[pid] = stack_base - pid * 8 * 1024 * 1024
# top of heap (breakpoint) # TODO: handled in load program
# memory maps: 1GB above top of heap
# mmap_start = mmap_end = break_point + 0x40000000
#---------------------------------------------------------------------
# stack argument initialization
#---------------------------------------------------------------------
# http://articles.manugarg.com/aboutelfauxiliaryvectors.html
#
# contents size
#
# 0x7FFF.FFFF [ end marker ] 4 (NULL)
# [ environment str data ] >=0
# [ arguments str data ] >=0
# [ padding ] 0-16
# [ auxv[n] data ] 8 (AT_NULL Vector)
# 8*x
# [ auxv[0] data ] 8
# [ envp[n] pointer ] 4 (NULL)
# 4*x
# [ envp[0] pointer ] 4
# [ argv[n] pointer ] 4 (NULL)
# 4*x
# [ argv[0] pointer ] 4 (program name)
# stack ptr-> [ argc ] 4 (size of argv)
#
# (stack grows down!!!)
#
# 0x7F7F.FFFF < stack limit for pid 0 >
#
# auxv variables initialized by gem5, are these needed?
#
# - PAGESZ: system page size
# - PHDR: virtual addr of program header tables
# (for statically linked binaries)
# - PHENT: size of program header entries in elf file
# - PHNUM: number of program headers in elf file
# - AT_ENRTY: program entry point
# - UID: user ID
# - EUID: effective user ID
# - GID: group ID
# - EGID: effective group ID
# TODO: handle auxv, envp variables
auxv = []
if EMULATE_GEM5:
argv = argv[1:]
argc = len( argv )
def sum_( x ):
val = 0
for i in x:
val += i
return val
# calculate sizes of sections
# TODO: parameterize auxv/envp/argv calc for variable int size?
stack_nbytes = [ 4, # end mark nbytes (sentry)
sum_([len(x)+1 for x in envp]), # envp_str nbytes
sum_([len(x)+1 for x in argv]), # argv_str nbytes
0, # padding nbytes
8*(len(auxv) + 1), # auxv nbytes
4*(len(envp) + 1), # envp nbytes
4*(len(argv) + 1), # argv nbytes
4 ] # argc nbytes
if EMULATE_SIMIT:
stack_nbytes[4] = 0 # don't to auxv for simit
def round_up( val ):
alignment = 16
return (val + alignment - 1) & ~(alignment - 1)
# calculate padding to align boundary
# NOTE: MIPs approach (but ignored by gem5)
#stack_nbytes[3] = 16 - (sum_(stack_nbytes[:3]) % 16)
# NOTE: gem5 ARM approach
stack_nbytes[3] = round_up( sum_(stack_nbytes) ) - sum_(stack_nbytes)
if EMULATE_SIMIT:
stack_nbytes[3] = 0
def round_down( val ):
alignment = 16
return val & ~(alignment - 1)
# calculate stack pointer based on size of storage needed for args
# TODO: round to nearest page size?
stack_ptr = round_down( stack_base - sum_( stack_nbytes ) )
if EMULATE_SIMIT:
stack_ptr = stack_base - MAX_ENVIRON
offset = stack_ptr + sum_( stack_nbytes )
# FIXME: this offset seems really wrong, but this is how gem5 does it!
if EMULATE_GEM5:
offset = stack_base
print "XXX", offset
stack_off = []
for nbytes in stack_nbytes:
offset -= nbytes
stack_off.append( offset )
# FIXME: this is fails for GEM5's hacky offset...
if not EMULATE_GEM5:
assert offset == stack_ptr
if debug.enabled( 'bootstrap' ):
print 'stack base', hex( stack_base )
print 'stack min ', hex( stack_ptr )
print 'stack size', stack_base - stack_ptr
print
print 'sentry ', stack_nbytes[0]
print 'env d ', stack_nbytes[1]
print 'arg d ', stack_nbytes[2]
print 'padding', stack_nbytes[3]
print 'auxv ', stack_nbytes[4]
print 'envp ', stack_nbytes[5]
print 'argv ', stack_nbytes[6]
print 'argc ', stack_nbytes[7]
# utility functions
def str_to_mem( mem, val, addr ):
for i, char in enumerate(val+'\0'):
mem.write( addr + i, 1, ord( char ) )
return addr + len(val) + 1
def int_to_mem( mem, val, addr ):
# TODO properly handle endianess
for i in range( 4 ):
mem.write( addr+i, 1, (val >> 8*i) & 0xFF )
return addr + 4
# write end marker to memory
int_to_mem( mem, 0, stack_off[0] )
# write environment strings to memory
envp_ptrs = []
offset = stack_off[1]
for x in envp:
envp_ptrs.append( offset )
offset = str_to_mem( mem, x, offset )
assert offset == stack_off[0]
# write argument strings to memory
argv_ptrs = []
offset = stack_off[2]
for x in argv:
argv_ptrs.append( offset )
offset = str_to_mem( mem, x, offset )
assert offset == stack_off[1]
# write auxv vectors to memory
offset = stack_off[4]
if not EMULATE_SIMIT:
for type_, value in auxv + [(0,0)]:
offset = int_to_mem( mem, type_, offset )
offset = int_to_mem( mem, value, offset )
assert offset == stack_off[3]
# write envp pointers to memory
offset = stack_off[5]
for env in envp_ptrs + [0]:
offset = int_to_mem( mem, env, offset )
assert offset == stack_off[4]
# write argv pointers to memory
offset = stack_off[6]
for arg in argv_ptrs + [0]:
offset = int_to_mem( mem, arg, offset )
assert offset == stack_off[5]
# write argc to memory
offset = stack_off[7]
offset = int_to_mem( mem, argc, offset )
assert offset == stack_off[6]
# write zeros to bottom of stack
# TODO: why does gem5 do this?
offset = stack_off[7] - 1
while offset >= stack_ptr:
mem.write( offset, 1, ord( '\0' ) )
offset -= 1
# initialize processor state
state = State( mem, debug, reset_addr=0x1000 )
if debug.enabled( 'bootstrap' ):
print '---'
#print 'argc = %d (%x)' % ( argc, stack_off[-1] )
#for i, ptr in enumerate(argv_ptrs):
# print 'argv[%2d] = %x (%x)' % ( i, argv_ptrs[i], stack_off[-2]+4*i ),
# print len( argv[i] ), argv[i]
#print 'argd = %s (%x)' % ( argv[0], stack_off[-6] )
print '---'
print 'envd-base', hex(stack_off[-7])
print 'argd-base', hex(stack_off[-6])
print 'auxv-base', hex(stack_off[-4])
print 'envp-base', hex(stack_off[-3])
print 'argv-base', hex(stack_off[-2])
print 'argc-base', hex(stack_off[-1])
print 'STACK_PTR', hex( stack_ptr )
# TODO: where should this go?
#state.pc = entrypoint
state.breakpoint = breakpoint
# initialize processor registers
state.rf[ 0 ] = 0 # ptr to func to run when program exits, disable
state.rf[ 1 ] = stack_off[6] # argument 1 reg = argv ptr addr
state.rf[ 2 ] = stack_off[5] # argument 2 reg = envp ptr addr
if EMULATE_SIMIT:
state.rf[ 1 ] = argc # argument 1 reg = argc
state.rf[ 2 ] = stack_off[6] # argument 2 reg = argv ptr addr
state.rf[ 13 ] = stack_ptr # stack pointer reg
state.rf[ 15 ] = entrypoint # program counter
if debug.enabled( 'bootstrap' ):
state.rf.print_regs( per_row=4 )
print '='* 20, 'end bootstrap', '='*20
return state